How to modify content of the original variable which is passed by value?

Question

There is an existing API function which does only allow the plugin(DLL) to receive three parameters and perform some action:

int ProcessMe(int nCommand, unsi         


        

Answer 1

Try this... it is POSSIBLE!!!

include

int ProcessMe(int nCommand, unsigned int wParam, long lParam)

{

int *nCommand_ptr = (int*)nCommand;
unsigned int *wParam_ptr = (unsigned int*)wParam;
long *lParam_ptr = (long*)lParam;
*nCommand_ptr = 10;
*wParam_ptr = 10;
*lParam_ptr = 10;
return 0;

}

int main(){

int nCommand = 5;
unsigned int wParam = 5;
long lParam = 5;
printf("\n %d %u %lu",nCommand,wParam,lParam);
ProcessMe((int)&nCommand,(unsigned int)&wParam,(long)&lParam);
printf("\n %d %u %lu",nCommand,wParam,lParam);
return 0;

}

Output:

$>g++ passbyref.cc

$>./a.out

5 5 5

10 10 10$>